Expression mechanism for self-playing musical instruments.



O. J; FAI RGHILD. EXPRESSION MECHANISM FOR SELF PLAYING MUSICALINSTRUMENTS.

APPLICATION FILED JULY 6,1908. Y 1,025,795. I Patented May 7, 1912.

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EXPRESSION MBGH Patented May 7-, 1912.

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APPLICATION FILED JULY6,19OB. 1,025,795. Patented May 7, 1912.

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O. J. PAIRGHILD. ANISM FOR SELF PLAYING MUSICAL INSTRUMENTS.

APPLICATION FILED JULZ6,1908.'

EXPRESSION MESH 1 ,025,795.'

0. J. FAIRGHILD. EXPRESSION MECHANISM FOR SELF PLAYING MUSICALINSTRUMENTS.

- APPLIOATION FILED JULY 6,1908 1,025,795.

Patented May 7, 1912.

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se mowmw a f I UNITED sTA'rns Parana? or OREN' J. FAIRCHILD, 0FBINGHAMTON, NEW YORK, ASSIGN'OR 0F GEE-HALF TO WILLIAM J. PAYNE, 0FCANDOR, NEW YORK.

EXPRESSION MECHANISM FOR SELFJPLAYING MUSICAL INSTRUMENTS.

Specification of Letters "Eatent.

Patented May *7, 1912.

Application tiled July 43, 1908. Serial No. 442,072.

To all whom it may concern:

Be itknown that I, OREN J. FAIRCHILD, a citizen of the United States,residing, at Binghamton, in the county of Broome and State of New York,have invented certain new and useful Improvements in ExpressionMechanism for Self-Playing Musical Instrmnents, of which the followingis a specification, reference being had to the drawings acconmanying andforming part of the same.

My invention relates toself-playing musi cal instruments, for examplepianos, of the soralled pneumatic typeth atis, in-

struments operated by pneumatic pressure in which the playinginstrumentalities are under the control of a perforated sheetor band of,generally, the usual kind.

The chief object of the invention, briefly stated, is to providemechanism forputting into the musical composition as played, what iscommonly called expression,in other words to provide mechanism, underthe control of the perforated tune sheet, for varying the loudness ofthe sound so as to make the music more effective or pleasing and tobring out, in a measure at least, the musical idea which a. musicalcomposition is supposedly intended to express.

Heretofore various means have been devised, and used with satisfactoryresults, for put-ting the expression under the control of the operator,who by the manipulation of suitable controlling devices can vary theloudness of the playing to suit his individual fancy. So far as I amaware, however, no thoroughly satisfactory means have been proposed forvarying the expression under the control of the tune-sheet; and this inspite of the fact that musical instruments, for example self-playingpianos, have been on the market for a considerable period, in which allthe functions-of the instrument are under the control of the tune-sheetwithout any attention on the part of an operator except merely to insertthe sheet and start the motor. My present invention there-forecontemplates the provision of expression mechanism for the purposereferred to,

which shall be thoroughly effective and reliable in operation andresult, and as simple and inexpensive as the nature of the case willpermit.

In carrying out my invention in the preferred manner I provide a bellowsor equivalent device, which from its purpose and function may beappropriately termed the fexpression bellows. This bellows is connectedboth to theair pump and to the socalled wind chest or vacuum chamber,whichlatter is operatively connected with the playing pneun'iatics.Being thus connected with the vacuum chamber-it is clear that anyexpansion of the bellows without the admission of air. thereto will havethe effectof increasing the vacuum in the vacuum chamber, causing theplaying pneumat-ics to be acted on more powerfully by the atmosphericpressure and hence causing harder blows to be struck on the strings andcorresponding louder sounds to be produced. On the other hand, it isequally effect will be to decrease the vacuum in the vacuum chamber andso result in softer playing; while if the valve be kept closed, so that.the pump can withdraw air from the expression bellows and vacuum chamberto a greater extent than the normal, the

loudness of the playing will be increased so long as the valve is keptin that condition. Thus by the expansion of the bellows without theadmission of air thereinto or into the bellows-vacuum-chamber system Iprovide for so-called acccnting, that is, for a quick and pronounced buttemporary increase in the loudness of the note or notes: while by thecontrol of the expression bellows valve I provide for a more sustainedincrease or decrease of loudness; it being understood of course that inany case the air pump continues to operate at its normal rate. Hence myinvention operates to produce expression in the playing of acomposition, not by cont-rolling the pump, as

by varying its speed or otherwise, but by varying the degree of vacuumin the vacuum chamber or wind chest through the iustrumentality of asuitable pneumatic device. namely, an expression bellows.

lVith this brief statement ofthe underlying principle of my invention,reference may now be made to the annexed drawings, which exhibit what Iconsider the best mode of applying that principle; it being understood,in this connection, that the devices illustrated, and now about to bedescribed more or less in detail, constitute merely the "preferredembodiment of the invention.

rious devices associated therewith.

' nectidn with the diaphragm-chambers, the

cording to the the devices device through 'by link 8 valves whichcontrol the diaphragms acexpression perforations in the tune-sheet. Fig.4 is a longitudinal sectional view of the expression bellows and mountedthereon, showing chiefly the air-valve, the diaphragms tor actuating orcontrolling the same and the operative connection between the phragmsand the valve. Fig. 5 is a sec tional view looking downward on line VVof Fig. 4-, showing the construction of the which the expression bellowsis pneumatically connected with the airpumpand the vacuum chamber. Fig.(3 is a diagrammatic sectional view showing the operative relationbetween the expression bellows and the parts pneumatically asso ciatedtherewith. Fig. 7 is a detail rear view of the accent device forexpanding the expression bellows. Fig. 8 is a section on line VHT-VTH ofFig. 7, looking down ward. Fig. 9 is a diagrammatic sectional view ofthe accent device, showing the operative relation of the parts thereof.

Referring new to Fig. 1, 1 designates the expression bellows, connectedby a tube 2 to the air-pump 3 and by a tube 4 to the vacuum chamber 5. lpneumatics are shown diagrammatically at 6, 6, mounted on the vacuumchamber.

7 designates the accent device, connected with the expression bellows toexpand the same, and 9 is the motor, driving the pump by a belt 10 whichalso engages the pulley 11 the accent device to actuate the same. The{tracker or duct-bridge 12 drawn. to a larger scale than the restof thefigure, may be located in any convenient and suitable posit-ion. lit isconnected to the expression bellows by tubes 13, 14, and to the accentdevice by a tube 15. The passages or apertures to which these tubes areconnected in the duct-bridge are preferably located at one end of thesame, as shown, and the corresponding edge of the tune sheet is applepriated to the perforations which coiiperate with such passages, suchperforations being arranged in three longitudinal lines, as will bereadily understood.

Referring now more particularly to Figs. 1 to 6, inclusive, theexpression bellows is removably secured in position on the piano dia-'bellows,

A few of the playing.

the said end in l case by means of its back or base 16, the lowerbeveled edge of which fits under a bar or strip 17 while the upper endis engaged by a lag-screw 18. In the top 19 of the bellows is an airvalve 20, having a stem 21, which latter is guided in its verticalmovement by a cover 22 over the aperture in which the valve works. Thisaperture is in communication with the atmosphere, above the valve, bypassages 22 extending laterally to the sides of the bellows-top, asSl10\ n in Figs. 2 and 4:. The upper end of the stem is engaged by alever 23, the other end of which is connected to a coil spring 2dcarried by a plate 25'on the overhanging arm 25 of a standard 26arranged alongside of the bellows. The lever 23 being pivot-allysupported between its ends, as at 27, it will be seen that the tendencyof the spring is to hpld the valve 20 closed and to expand the and thatthe tension of the spring can be' varied by screwing it in or out of itssupporting plate, thereby varying the force exerted on the valve and thebellows. The hook 28, by which the spring'is connected to the lever, isformed on a strip or bar 29 which is adjustable lengthwise. of the leverunder the pivot 27 and under the setscrcw30, so that by adjusting thehook to- .ward or from the pivot the tension on the valve stem can beregulated independently, to a certain extent, of the tension on thebellows. lVhen the hook is properly adjusted the screw'30 is tightenedup, thus binding the two sides of the lever firmly on the hook andholding the same securely in position, as will be readily understood.

, The lower end of'the valve stem bears on the end of a lever 31 pivotedat 32 on the underside of the bellows-top and extending toward the hingeend of the bellows. Bearing on the end of the lever 31 adjacent to ofthe bellows is a stem 33 slidable in the bellows-top and bearing at its.upper end against an airtight movable dia- 1 phragm 3d. The latter 1sarranged in a' space formed partly in the bellows-top and partly in ablock 35 secured on the bellows top, and divides. the said space intotwo' chambers 36, 37, as shown. In the upper side of the block is athird chamber, 38 separated-from chamber 37 by a partition 39 andclosed. by a diaphragm 4.0. Slidably mounted in the said partition is. apin a1, bearing on the diaphragms 34-, 40. It may here be stated thatchamber 36 is in constant con1-- munication with the interior of thebellows through a minute aperture or passage 42 in the bellows-top;while chambers .37 and 38 are normally in communication with theatmosphere but .nay, by the means hereinafter described, be wt. indirect'connection with the air pump.

From the foregoing it will be evident that since'thcre is/a partialvacuum in chamber 36, the pressure of the atmosphere, exerted on the topof diaphragm 34, tends to open the valve 20 against the tension ofspring vacuum in the bellows is increased to or above,-a predeterminedpoint. Thus the degree of vacuum in the bellows is normally preventedfrom rising above a certain point-determined by the tension exerted onthe valve 20 by the spring 24since the instant such point is reached thediaphragm 34 depresses the pin 33 and raises the valve through theinstrumentality of the lever 31. On the other hand, it is equally clearthat if the chamber 37 be put' in communication with the pump, so thatthe pressure in said chamber will be reduced by exhaust-ion of airtherefrom, the pressure in the bellows may fall lower than normalwithout causing the'valve 20 to be opened. So'long as chamber 38 is incommunication with the atmosphere the pressure is the same on both sidesof diaphragm 40, and hence the latter has no effect on the lever 31 andvalve 20; but

if now the chamber 38 be put in communication with the air-pump, theexcess of the atmospheric pressure on top of the diaphragm 40 over thelessened pressure in chamber 38 will depress the diaphragm and so raisethe valve 20 against the tension of spring 24. It will therefore beclear that (1) diaphragm 34, when both chambers 37 and 38 are incommunication with the atmosphere, automatically prevents the pressurein the bellows from falling below a predetermined limit; that (2) whenchamber .37 is put in communication with the pump the diaphragm 34 willnot open the valve 20 when the pressure in the bellows falls belownormal; and that (3) when chamber 38 is put in communication with thepump the diaphragm 40 positively opens the valve 20 and thus causes thepressure in the bellows to stand higher than normal.

The operation of the diaphragms 34 and 40, to vary the loudness of theplaying, is placed under the ultimate control of the tune-sheet. Forthis .purpose a pair of valves 43, 44 are provided in the block 35,shown best in Figs. 3 and 6. Each of these valves comprises fourchambers, 45, 46, 47, 48, the last two being separated by a movableair-tight diaphragm 49 carrying a valve disk 50 arranged to cooperatewith either of the apertures in partitions 51, 52 between chambers 46and 47, and 'chambers'45 and 46, respectively. Chambers 47 i are incommunication with a passage 53 in the block 35, which passage isconnected wit-l1 the pump through a tube 54 in the manner hereinafterdescribed. Chamber 46 of valve 43 is connected to diaphragm chamber 38,and chamber 46 of valve 44 is connected with diaphragm chamber 37, asshown. Both valve chambers48 are connected to the passage 53 throughminute apertures or vents 55, and to the duct-bridge or tracker by thetubes 13, 14. Chambers 45 are in communication with the atmospherethrough ports 58.

From the foregoing the operation of the valves in controlling thediaphragms 34, 40, will be readily understood. Assume, for example thata perforation inthe tune sheet comes over the duct-bridge passage towhich the tube 13 is connected. Since the chamber 48 (of valve 43) is incommunication with the pump, a partial vacuum exists above as well asbelow diaphragm 49 and in consequence the atmospheric pressure on valvedisk 50 holds the latter over the aperture in partition 51. But when aperforation in the tune sheet admits air to the chamber 48, thediaphragm 49 is depressed carrying with it disk 50 which thereuponcloses the aperture in partition 52.. This cuts off communicationbetweendiaphragm chamber 38 and the atmosphere and establishes communicationbetween said chamber and the pump. A partial vacuum is thereforeproduced in diaphragm chamber 38, with consequent opening of 'thebellows valve 20 as previously described causing the instrument to playsoftly. It is clear that if the perforation in the tune sheet be small(or short) the tube 13 will be open only momentarily; hence only arelatively small quantity of air will be admitted to the bellows beforethe valve 20 is closed again on account of the reverse operation ofvalve 43; with the result that the decrease in the loudness of theplaying will be correspondingly slight, and short in duration. On theother hand if a succession of short perforations passes over theductbridge passage to which tube 1.3 is connected the duration of thesoft playing will be correspondingly lengthened. If the perforations inthe tune sheet are each longer,

the valve 20 will be open for a longer time at each passage of aperforation over the duct-bridge, more air will be admitted to thebellows at each opening of valve 20, and

hence the playing will be still softer. Bv

a similar operation of valve 44, diaphragm 34 is raised for longer orshorter periods,

thus causing forte or crescendo effects.

Thus by varying the length and number of 5 the expression perforationsin the tune sheet various piano, diminuendo, forte, and

crescendo effects may be produced, as will be readily understood. Forproducing a quick and loud or fortisl3 belt 10, and a fly-wheel or diskair-tight simo Iefiect in'the playing, the device illustrated moreclearly in Figs. 7, 8 and 9 is provided, which will now be described.Mounted in suitable bearings 59, 60, between the air pump and theinotor(see Fig. 1) is a shaft 61 on which are rigidly mounted the drivingpulley 11, in engagement with 63. Adjacent to the flat sides of thewheel but normally spaced therefrom by springs '63, are two disks orplates 64:, 65, o f stiff sheet metal, connected at their edges byaflexible band 66 of leather or other suitable material, to form-an airtight casing inclosing the fly-wheel, the said disks 64, 65 beingmounted on the shaft 61 to permit rotation thereof without movement ofthe disks or admission of air into the casing.

One of the disks, as 6-1, is connected by the ink 8 (see Fig. 1) to theexpression bellows 1. It will now is exhausted from the wheel casing theexternal atmospheric pressure will press the disks into firmfrictional-contact with the wheel, causing the disks to move with thewheel and, through the instrumentali ty of link 8, quickly expanding theexpression bellows without opening the valve 20. The result, aspreviously described, is to greatly increasethc vacuum in the bellowsand vacuum chamber and hence cause the play ing pneumatics to operatewith correspondingly greater force. This operation of the wheel casingis effected under the control of devices now to be described.

Mounted loosely on the shaft 61, adjacentto the disk (35, is a block 67,provided with a chamber 68 aroundthe shaft and in communication with theinterior of the wheel casing through one or more apertures 69. Theclian'iber (38 is also in communication through a passage 70 withseparated "from a second ch mber 72 by a. movable air-tight diaphragm73. The other wall of the chamber 72 has a small diaphragm 74: connectedtoa lever 75' which carries ,at its free end a valve-disk or cover 76tocooperate with an opening 77.1nto

the passage 70. The block 67 also carries a valve pneumatic 78 (Figs. 7and 9). comprising three chambers, 79, 80, 81. The first-79 of thesechambers is connected to chaniber 72 by a passage 82;-the second 80 isconnected to the pump "by the tube 82*, and through a minute aperture orvent 83 to a passage 84: which is in turn connected to the duct-bridgethrough the tube '15, (Figs. 1 and 7) and the third chamber 81, theouter wall of which is formed by a diaphragm 85, is connected to thepassage 84 as shown. The walls of chamber 79 are provided with centralopenings with which a valve disk 86 cooperates, said valve having a stem87 bearing on diaphragm 85.

The operation of the mechanism above:

be evident that if the air a chamber 71 described will now be readilyunderstood. Since chambers 79, 80 and 81 are in communication with thepumps, it is evident that so long as the passage 84 is kept closed atthe duct bridge the same degree of vacuum will exist in all threechambers and hence atmospheric pressure on diaphragm 85 will hold thedisk 86 in the position shown in Fig. cation between chamber 7 2 and thepump through chamber 80 and tube 82*. ,It' now 9, opening communianaperture in the tune-sheet opens passage 84, air will be admitted intochamber 81 faster than it can escape through veut83 to the pump. Thisrelieves the vacuum in 81,

with the result that the valve 86 is reversed, V as will be readilyunderstood, closing coihmunication between chambers 79 and 80 andopening passage 82 to the air. This permits the spring 88 to pressdiaphragm 7 3 toward the opposite wall of chamber 71, the air escapingfrom 71 through passage 70 and aperture 77 into the atmosphere. Thismovement of the diaphragm continues until the limit of its movement isreached, or until closed if that the duct-bridge passage is occursbefore the former. Vilhen the duct bridge passage is closed the air ispromptly exhausted from chamber 81 by the pump through vent 83, thusrestoring the valve disk 86 to its normal position. Chamber 72 beingthus put again into communication with the pump, the chamber isinstantly exhausted of air, causing diaphragm 74c to bring the cover ordisk 76 down over aperture 77 and drawing the diaphragm 73 back to itsnormal position. This movement of the latter diaphragm 73 causes a quickexhaustion of air from the fly-wheel casing, thus permitting theatmosphere to press the casing disks into engagement with the wheel andcausing a sudden expansion of the expression bellows, as previouslydescribed. The actuation of the link 8, however, continues'only untilthe stem 89 on diaphragm 78 engages the diaphragm 74 and so raises thelever 75, uncovering aperture 77 and restoring atmospheric pressure tothe wheel casing, whereupon the springs 63 throw the disks 6 1, 65 outof contact with the fly wheel. in this manner each uncovering of theduct-bridge passage to which valve 7 8 is connected produces a quick andmomentary expansion of the expression bellows, and a correspondinglymore powerful operation of the playing pneu1natics. The extent of suchexpansion of the bellows, and hence the force with which the playing,pneuuiatics operate, plainly depend upon the length of time during whichthe fly wheel casing iscollapsed, which in turn depends upon the timerequired for the dia phragm 7 3 toreturn to its normal position and openaperture 77. Thus if the perforation in the tune sheet is long enough tokeep 12 valve 7 8 reversed until diaphragm 73 moves to its limit oftravel, a longer time will be required for the said. diaphragm to returnand open aperture 77, and the link 8 will have a correspondingly longermovement. On the other hand, if the tune-sheet perforation is veryshort, only slight movement of the diaphragm 73 can occur. Hence byproperly proportioning the length of' the perforations the degree offorce imparted to the operation of the playing pneumatics maybe variedas desired, while any number of successive notes may be accented by proriding the proper number of such perforations, as will be readilyunderstood.

The device through which the expression bel ows is connected to the pumpand to the vacuum chamber will now be described. Mounted transversely onthe back plate 16 (Figs. 2, 4;, 5 andtl) at the hinge end of theexpression bellows is a block 90, provided with a passage 91. At one endthis passage is in communication with the expression bellows 1 through agroove in the base or back-plate, indicated. in dotted lines at 92, Fig.4, and at its other end the passage is connected to the vacuum chest bythe tube 1 (Fig. 1). Extending longitudinally of the block is a chamber93 (Fig. 6) connected with passage 91 by way of a small chamber 91 andpassage 95. Separated from the chamber 94 by a partition 96 is anothersmall chamber 97, closed by a movable air-tight diaphragm 98, but incommunication with passage 93 by an opening 99. Between the chamber 94and passage 93 is a valve 100, the stem of which extends up throughpartition 96 into engagement with a diaphragm 98. This valve is normallyheld closed-by a spring 101, supported by a pin 102 and having its endbent into engagement with a screw 103 by which the tension of the springon the valve may be regulated as desired. At the endof the block inwhich the said screw is fitted the passage 93 is connected with the tube2 (Fig. 1) which leads to the air pump. From the same part of the saidpassage the tube 54 leads to the passage in the block 35, and othertubes, as 101:, 10-5, lead to the so-called accessory pneumatics, whichoperate the piano pedals, hammer rail, etc. The operation of the valve100 will now be described. Tube 2 being connected with the pump, it isclear that-the maxin'mnr degree .of vacuum of which the pump is capablewhen in normal operation will be produced in. passage 93 and chamber 97.rrssuming that the expression bellows contains air at atmospheric pressure, as will be the case when the pump is first started, it will beseen that the pressure of the air in chamber 94 and on diaphragm 98will, as soon as the pressure .in 93 and 97 has fallen low enough, openor de- =-press valve 100 against the tension of spring 10].. Air willthen be drawn out of the bellows 1 and the vacuum chamber 5 until thepressure therein, plus the atmospheric pressure on diaphragm 98, isinsufficient to open" valve '100 against its spring and the pressure ofthe residual air ,in 93 and 97. As the playing pneumatics come intooperation it is clear that'air will be admitted therethrough intothevacuum chamber and expression bellows, and hence by increasingthepressure therein, would'cause the valve 100 to be again opened. Inthe meantime,- however, the pedal, hammer-rail, or other accessorypneumatics come into operationand the air which they receive from theduct-bridge. of course flows to passage 93,

' increasing the pressure therein and aiding the spring 101 to keep thevalve 100 closed until the pump can lower the pressure in 93. It willtherefore be seen that by the operation described the accessorypneumatics, which in general require more, power than the playingpneumatics for satisfactory operation, are assured of having .the properdegree of vacuum 7 inv them, depending upon the tension of spring-101 asadjusted by the screw 103. In other words, no matter what the pressurein the expression bellows 1 may be, whether above or below the" normal,the valve 100 will not openunless the partial vacuum in the passage 93and the accessory pneumatics is sufiicient to insure the properoperation of the latter.

In playing a long passage softly it may happen that so much air may beadmitted to the expression bellows by the valve 2021s to makethe partialvacuum in the bellows and vacuum chesttoo slight for the properactuation of the playing. pneumatios. In order to avoid this possibilitymeansr'are provided as follows in connectionwith the bellows In the topthereof is a chamber 106 (Fig. 4) closed by a diaphragm107, and

in communication with the interior. of the bellowsby a vent or minutepassage 108. This diaphragm is connected to a lever 109' urged outwardlyfrom the bellows-top by a flat springllO, the tension of which can beregulated by a screw 111. 'On the free end of the lever is a valve diskor cover'l12 adapted to close the mouth of a passage 113 connected by atube 114 to the tube 14 which connectsthe valve 44 with the duct bridge.Since the chamber 106 is in communication with'the interior, of thebellows the pressure in said chamber and bellows 1s the same, and thediaphragm 107 is depressed by the pressure of the atmosphereagainst thetension of spring 110, carrying the disk 112 down upon the mouth of thepassage 113. If now the pressure in the bellows,

and hence in chamber 106 also, should rise to a certain point,determined by the adjustment of spring 110, the latter will raise thelever and open passage 113, thereby ad- K mitting air to chamber 48 ofvalve 44 which controls diaphragm 34a The result is that the latterdiaphragm is raised, which movement, it will be remembered, permitsvalve 20 to be kept closed by the spring 24. .Thus no more air can enterby way of valve 20 until the normal degree of vacuum is restored in thebellows and in chamber 106; whereupon the passage 113 is closed again bydisk 112, with the same efiect on valve 44 and diaphragm 34 as has theclosing of the duct-bridge passage with which said valve is connected.

The mechanism herein illustrated and de scribed has been found inpractice to be thoroughly effective, being positive and cer tain, yetdelicate, in operation, affording pleasing variation of expression inthe playing of a composition. Moreover, it can be applied to existinginstruments with no, or at most but slight alteration in the playingmechanism.

As previously stated, the form shown is merely the preferred embodimentof the invention, which may be embodied in other specific forms withoutdeparture from its proper scope as defined by the appended claims.

I am aware that there are instances in the prior art of expressionregulators which however, perform only the functions ofvalve actuatingpneumatics, corresponding to the pneumatics described herein and shownin Fig. at at 34: to 41. It will be sufficiently apparent after readingthe foregoing specification that my invention performs additionalfunctitms, by means of novel' mechanism operated in animproved manner. Iwish to claim the differences broadly, and in so doing I shall use theterm expression bellows, to indicate a bellows of variable pressure,-acting as' a receiver for the air exhausted from the strikingpneumatics, under control which is entirely independent of the regularsustaining bellows, or the constant action of the pump.

What I claim is:

1. In a self playing musical instrument. the combination with aduct-bridge, a vacuum chamber, and an air pump, of an expression bellowsconnected with the pump and the vacuum chamber, a valve for admittingair into said bellows, a. pair of diaphragms operatively connected withsaid valve. one arranged to open the valve to admit air to the bellows,and the other arranged to disconnect the first from its op erativeconnection with the valve, and pneumatic means connected with theduct-bridge for controlling said diaphragms, as set forth. 5 I

2. In a self playing musical instrument, the combination of anexpression bellows, yielding means tending to expand the be llows, avalve to admit air to the bellows but norm ally held closed by saidyielding means, and pneumatically actuated devices for opening saidvalve against the tension of said yielding means.

3. In a self-playing musical instrument, the combination with a vacuumchamber, an air pump, and a duct-bridge, of an expression bellowsseparate from but pneumati-- cally connected with the vacuum chamber andconstituting an auxiliary pressure source independent. of the air pump,means for applying power to said bellows, and pneumaticmcans connected,with the duct bridge for controlling said first means, as set forth.

*1. In a self-playing musical. instrument, the combination with a vacuumchamber, an air pump, asourceof power therefor, and a duct-bridge, of anexpression bellows separate from but pneumatically connected with thevacuum chamber, a power-driven element, operating mechanism intermediatebetween the saidelement and the bellows to apply power to the same,including a' menf ber adapted to engage the power-driven ele ment'so asto be actuated thereby, and pneu matically operated means connected withthe duct-bridge for causing momentary engagement of the said member withthe power-driven element, as set forth.

5. in a self-playing musical instrument,v

the combination with a tracker bar, pneumatic playing instrumentalitics,a note sheet cooperating with the trackerbar, and a pump to exhaust airfrom the playing instrumentalities, of a. separate expression bellows inpneumatic communication with said instrumentalities and with the pump,and pneumatically controlled means under the control of the tracker barand note sheet to apply power for suddenly expanding said bellowsagainst its closing movement caused. by the exhaustaction of the pump.

6. In a self-playing musical instrument, the combination with a trackerbar, pneumatic playing instrumcntalities, a note sheet coiiperating withthe tracker bar, and a pump to exhaust air from theplaying-instrumentalities, of a separate expression bellows'in pneumaticcommunication with theinstrumentalities and with the pump, an inletvalve for said bellows, pneun'iatically controlled means controlled bythe note sheet and tracker bar for operating said valve, andpneumatically operated means also under the control of the note sheetand tracker bar to apply power for suddenly expanding the expressionbellows against its closing movement caused by the exhauststrumentalities, of a separate expression bellows in pneumaticcommunication with said instrumentalities and with the pump, means toactuate said expression bellows by power derived independently of itspneumatic connections, an inlet valve for the bellows, a lever engagingsaid valve, and pneumatically actuated means controlled by the notesheet and tracker bar for swinging said lever to open the valve.

8. In a self-playing musical instrument, the combination with a trackerbar, pneumatic playing I instrumentalities, a note sheet cooperatingwith the tracker bar, and a pump to exhaust air from the playinginstrumentalities, of a separate expression bellows separate from butvin pneumatic communication with said instrumentalities and with thepump, means to actuate said expression bellows by power derivedindependently of its pneumatic connections, an inlet valve for thebellows, a lever engaging said valve, means for normally maintaining thevalve closed, and pneumatically actuated means cont-rolled by the notesheet and tracker bar for swinging said lever to open the valve.

9. In a self-playing musical instrument, the combination with a trackerbar, pneumatic playing instrumentalities, a note sheet jcooperating withthe tracker bar, and a pump to exhaust alr from the playing instrumentalities, of an expression bellows separate from but 1n pneumaticcommunication wlth' the said lnstrumentalitles and with the pump, meansto actuate said expression bellows by power derived independentl} of itspneumatic connections, an inlet valve for said bellows, a lever engagingthe valve, a spring engaging the lever to urge the valve to its seat,and pneumatically operated means under the'control of the tracker barand note sheet for operating said valve to admit air to the bellows.

10. In a self-playing musical instrument,

I the combination with a tracker bar, pneumatic playinginst-rumen'talities, a note sheet cooperating with the tracker bar, anda pump to exhaust air from the playing instrumentalities, of anexpression bellows communicating with said instrumentalities and thepump, an inlet valve 'for said bellows, a lever engaging the valve, saidlever being composed of parts adjustable with relation to each other,one of which engages the valve,'a spring engaging another of said partsto swing the leverto urge the valve to its seat, and pneumaticallyoperated means under the control of the tracker bar and.

note sheet. for operatingsaid valve to admit air to the bellows.

11. In a self-playing musical instrument, the combination with a trackerbar, pneumatic playing instrumentalities, a note sheet cooperating withthe tracker bar, and a pump to exhaust air from the playinginstrumentalities, of an expression bellows communicating with the saidinstrumentali-' ties and the pump, an'inlet valve for said.

bellows, a spring acting upon the valve and pump to exhaust air from theplaying instrumentalities, of an expression bellows communicatingwiththe said instrumentalities and the pump,;an inlet valve for saidbellows, a lever engaging the valve, said le-' ver comprisinglongitudinally slidable parts adjustable relative to each other toregulate the length of the lever, one of said parts ene gaging thevalve, a spring engaging the otherof said parts to urge the valve to itsseat, and pneumatically operated means under the control of the notesheet and the tracker bar'for operating said valve to admit air to thebellows.

13. In a self-playing musical instrument,

the combination with a tracker bar, pneumatic playing instrumentalities,a note sheet cooperating with the tracker bar, and-a pump to exhaust airfrom the playing incat-ion with the said instrumentalitiesand with thepump, means for driving said bellows independently of said pneumaticcommunications, an inlet valve for said bellows, pneumatically operatedmeans under control of the note sheet for opening saidvalve, andadditional means independent of the sheet and tracker for closing thevalve when the degree of vacuum in the expression bellows falls below apredetermined point.

14; In a self-playing musical instrument, the combination with aftrackerbar, pneumatic playinginstrumentalities, anote sheet cooperating withthe tracker'bar, and a pump to exhaust air from the playinginstrumentalities, of an expression bellows communicating with saidinstrumentalities and the pump, an inlet valve for the be].- lows,pneumatically controlled means for opening the valve when the degree ofvacuum in the bellows increases beyond a predetermined point, and meansunder the control of the notesheet and tra'cker bar for rendering saidpneumatically operated means ineffective to open the valve.

15. In a self-playing musical instrument, the combination with'a trackerbar, pneumatic-playing inst-rumentalities, a note sheet cooperating withthe tracker bar, and a strumentalities,1of a'separate-power driven 1expression bellows in pneumatic communi- I lows constituting pump toexhaust air from the playing instrumentalities, of a separate expressionbelvice communicating with the said instrumentalities and the pump, arotary driving element, means r'or rotating the same, and means forcoupling the expression bellows to said element whereby the latterapplies power to impart a quick opening movement to the bellows.

16. In a self-playing musical instrument,

the combination with a tracker bar, pneumatic playinginstrument-alities, a note sheet cooperating with the tracker bar, and apump .to exhaust air from the playing instrumentalities, of a separateexpression bellows constituting an auxiliary exhaust devicecommunicating with the said instrumentalities and the pump, a rotarydriving element, means for rotating the same, means for coupling theexpression bellows to said element whereby the latter applies power toimpart a quick opening movement to the bellows, and pneumaticallyactuated means For operating said coupling means.

17. In a self playing musical instrument, the combination with a trackerbar, pneumatic playing instrumentalities, a note sheet cooperating withthe tracker bar, and a pump to exhaust air fromtheplayinginstrumentalities, of a separate expression bellowsconstituting an auxiliary exhaust device communicating with the saidinstrumentalities and the pump, a rotary driving element, means forrotating the same, means for coupling the-expression bellows to saidelement whereby the latter applies power to impart a quick openingmovement to the bellows, and pneumatically actuated means under thecontrol of the note sheet and tracker bar for operating said couplingmeans. I 1

18. In a self-playing musicalinstrument, the combination with a trackerbar, pneumatic playing instrumentalities, a note sheet cooperating withthe tracker bar, and a pump to exhaust air from the playininstrumentalities, of an expression befiows communicating with. the saidinstrumentali-f ties and-the pump; a rotary element, means for rotatingthe same, a collapsible chamber surrounding said element, saidchamber being connected to the expression bellow, and means for collapsing .saidchamber to couple it to said rotary element to move therewith toimpart'an opening movement, to the bellows.

19. In a self-playing musical instrument, the combination with a trackerbar, pneumatic playing instrumentalities, a note sheet cooperating withthe tracker bar, and a pump to exhaust air from the playinginstrumentalities, of an expression bellows communicating with the saidinstrumentali ties-and the pump, a rotary element, means an auxiliaryexhaust de,

of the notes, sheet and tracker whereby the pressure in to rotate thesame, a collapsible chamber surrounding said element, said chamber beinconnected to the expression bellows, an means for exhausting air fromthe chamber tocause it to collapse into engagement with said element andmove therewith to impart an opening movement to the bellows.

20. the combination with a tracker bar, pneumatic playinginstrumentalities, a note sheet cobperating with the tracker bar, and apump to exhaust air from the playing instrumentalities, of an expressionbellows communicating with the said instrumentalities and the pump, arotary element, means to rotate the same, a collapsible chambersurrounding said element, said chamber being connected to the expressionbellows, and pneumatically operated means for exhausting air from thechamber to cause it to collapse into on agement with said element andmove therewith to impart an opening move ment to the bellows.

21. In a self playing musical instrument,

the combination with a tracker bar, pneumatic playing instrumentalities,a note sheet cooperating with the tracker bar, anda pumpj-o exhaust air"from the playing instrumentalities, of an expression bellowscommunicating with the said instrumentalities and thepum'p, a rotaryelement, means to rotate the same, a collapsible chamber surroundingsaid element, said chamber being connected to the expression bellows,and neumatically operated means under control N bar for exhausting air,from the chamber to cause it to collapse into engagement with saidelement and move therewith to impart an opening movement to the bellows.p

22. In a self-playing musical instrument, the combination with a trackerbar, pneumatic playing instrumentalitiesa note sheet cooperating withthe tracker bar, and a pump to exhaust air from the playinginstrumentalities, of an expression bellows communicating with saidinstrumentalities and the pump, means under the control of the.notesheet and tracker bar for admitting air directly to the bellows, andmeans exposed to the pressure inthe bellows adapted to act upon andregulate said air'control, the bellows may be maintained approximatelyconstant.

23; In a self-playing musical instrument, the-combination with atrackerbar, pneumaticplaying instrumentalities, a note sheet cdoperating withthe tracker bar, and a pump to exhaust air from the playinginstrumentalities, or" an expression bellows communicating with the saidinstrumentalities and the pump, a rotary ele ment, means for rotatingthe same, a collapsible chamber surrounding said element, said chamberbeing connected to the expression bellows,

In a self-playing musical instrument,

the bellows,

means for collapsing said chamber to couple it to said rotary element tomove therewith to impart an opening movement to the bellows, and meansfor expanding said chamber out of engagement with the rotary element.

24. In a self-playing musical instrument, the combination with a trackerbar, pneumatic playing instrument-alities, a note sheet cotiperatingwith the tracker bar, and a pump to exhaust air from the playininstrumentalities, of an expression be lows communicating with the saidinstrumentalities and the pump, means for rotatin the same, acollapsible chamber surroun ing said element, said chamber beingconnected to the expression bellows, means for collapsing said chamberto couple it to the rotary element to move therewith to impart anopening movement to and a spring for expanding said chamber out ofengagement from the rotary element.

25. In a self playing musical instrument,

' strumentalities,

a rotary element,

the combination with a tracker bar, pneumatic playing instrumentalities,a note sheet cooperating with the tracker bar and a pump to exhaust airfrom the playing inof an expression bellows communicating with the saidinstrumentalities and the pump, a rotary element, means to rotate thesame, a collapsible chamber surrounding said element, and means forexhausting air from the chamber to cause it to collapse into engagementwith said ele ment and move therewith to impart an opening movement tothe bellows, said exhaustmg means comprising an air chamber hav ing amovable wall and pneumatically operated means for controlling themovements of said wall to draw the air from the collapsible chamber.

GREN J.. FAIROHILD.

Witnesses;

HARRY G. PERKINS, M. P. HOWARD.

